A wide variety of machinery exists in working conditions throughout the world which is exposed to abrasive and stressful conditions. Large work loads, open and corrosive conditions and time all work to wear-out bearing surfaces and require replacement and/or repair. For large bearing surfaces, there is often a need to buildup material in the inner surface of the bearing bore. Various attempts have been made to provide automated machinery for depositing welding beads in a uniform manner on the inner bores of bearing journals.
For instance, U.S. Pat. No. 4,527,039 to Fuwesi teaches an apparatus and method for restoring blind or through surfaces of metallic work pieces. Fuwesi teaches a method by which tools, including welding torches, can be connected to a rotating spindle. The effective radii of rotational movement of the welding torch in Fuwesi is fixed by a combination of the length of the welding attachment itself and the spindle mechanism. Fuwesi does not disclose a manually adjustable axial positioning mechanism.
U.S. Pat. No. 4,687,899 issued to Acheson teaches an apparatus for restoring the inner surfaces of bores in metallic workpieces that has an adjustment means that relies on fixed pieces connected with a gear mechanism for adjusting the effective radii of the welding torch. This mechanism will be either quite large or will have a small range of adjustable radii. As another embodiment of Acheson""s apparatus, there is a provided a two part mechanism for adjusting the radius of the welding arm, a radial arm and an arm parallel to the axis of rotation of the axis of the apparatus. It is clear that Acheson requires several embodiments of the device in order to provide a wide range of radii.
U.S. Pat. No. 5,298,710 issued to Acheson also teaches an apparatus for building up material in a large bore of a metallic work piece. In developing the Acheson technology of previous patents, including U.S. Pat. Nos. 4,873,419; 4,892,990; and 4,952,769; Acheson has relied upon additional setups to provide a greater radii range and about 360 degrees of rotation and then makes an axial step, effectively equal to a width of the welding bead.
The typical trend has been to make devices that are capable of doing many operations, including building up bore surfaces and little attention has been paid to providing equipment that is responsive to the needs and conditions imposed by day to day operations. However, none of the prior art references are specifically configured to be easy to set up in the field, which typically is their primary working condition. Each of the known systems is complicated and requires careful attention to setup parameters in order to insure proper operation. The present invention is designed to allow easy setup and use through means of easy adjustment of the apparatus, manual adjustment of the significant positioning parameters, simple linear controls to adjust process parameters of the buildup process, and, relatively small size.
It is an object of the invention to provide a device for uniformly building up the inner surface of a bore and which is easy to setup.
It is a farther object of the invention to provide an apparatus that provides a very uniform buildup of material on the inner surface of a bore.
It is also an object of the invention to provide an apparatus for the buildup of material that is easy to position and reposition or to change the direction of the movement of the apparatus along an axis.
It is also an object of the invention to provide an apparatus that will create a spiral buildup mechanism, simple manual axial adjustment, and simple manual radial adjustment.
Furthermore, it is an object of the invention to provide linear adjustment of a buildup rate and a sweep rate of the apparatus during operation.
The present invention relates to an automated welding device used to build up material on the inner surface of a bore so that the bore can be restored to its original working order. The apparatus is characterized in having various improvements over the state of the art devices specifically including a welding extension arm that has a first and second hollow arm joined with a swivel bearing that allows radial adjustment of a welding torch that extends from the second hollow arm; a unitary mechanical mechanism that coordinates the rotation of the welding arm and the axial movement of the welding torch; a manually releasable mechanism for adjusting the initial radial position of the welding arm and readjustment of the same; and a conductive path that provides current flow in an external portion of the device is limited to the swivel bearing and the second hollow arm of the welding torch arm. Furthermore, the welding core assembly which carries the welding component.